In iOS development, managing network requests efficiently is crucial to performance and user experience. However, with operating system updates, developers often need to adjust their code to align with deprecations and new best practices. When iOS 9 was released, the sendAsynchronousRequest:queue:completionHandler: method was deprecated. This article will guide you on updating your code to work with the newer APIs available.

Understanding the Deprecation of sendAsynchronousRequest

Introduced as a part of NSURLSession, the sendAsynchronousRequest:queue:completionHandler: method allowed you to perform network requests asynchronously. In iOS 9, this method was deprecated in favor of more sophisticated and modern NSURLSession APIs.

Why Was It Deprecated?

1. Flexibility and Extensibility: NSURLSession offers a more robust and flexible framework for handling network requests. With capabilities such as download tasks, upload tasks, background sessions, and more, NSURLSession provides detailed control over request execution.
2. Improved Resource Management: NSURLSession supports configuration objects, allowing for better resource and session management, which is crucial for applications dealing with multiple network requests.
3. Concurrency: The newer APIs handle concurrency more robustly, taking advantage of GCD and NSOperationQueue to manage tasks in a more efficient manner.

Altering Code to NSURLSession

Transitioning from sendAsynchronousRequest to NSURLSession requires some changes in your approach. Here’s how you can modify your code:

Old Approach

Using sendAsynchronousRequest:

• Usage of NSURLSession: The NSURLSession instance manages the session. In the new approach, session is a shared session used for simple tasks that do not require any custom configuration.
• Data Task Creation: Unlike sendAsynchronousRequest, which directly handles the request, NSURLSession requires creating a NSURLSessionDataTask.
• Initiating the Request: After creating a task, the developer must explicitly start it using [dataTask resume];.
• Detailed Control: You get more granular control over tasks, better customization options, and the ability to handle different types of network tasks.
• Efficient Resource Use: NSURLSession efficiently manages network resources and caches, leading to optimized performance.
• Support for Background Tasks: With its background session configuration, you can perform network operations even when the app is backgrounded, ensuring that critical updates do not interrupt the user.